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91.
BACKGROUND AND OBJECTIVES: The detection of recombinant human erythropoietin (r-HuEPO) abuse by athletes remains problematic. The main aim of this study was to demonstrate that the five indirect markers of altered erythropoiesis identified in our earlier work were reliable evidence of current or recently discontinued r-HuEPO use. A subsidiary aim was to refine weightings of the five markers in the initial model using a much larger data set than in the pilot study. A final aim was to verify that the hematologic response to r-HuEPO did not differ between Caucasian and Asiatic subjects. DESIGN AND METHODS: Recreational athletes resident in Sydney, Australia (Sydney, n = 49; 16 women, 33 men) or Beijing, China (Beijing, n=24; 12 women, 12 men) were randomly assigned to r-HuEPO or placebo groups prior to a 25 day administration phase. Injections of r-HuEPO (or saline) were administered double-blind at a dose of 50 IU/kg three times per week, with oral iron (105 mg) or placebo supplements taken daily by all subjects. Blood profiles were monitored during and for 4 weeks after drug administration for hematocrit (Hct), reticulocyte hematocrit (RetHct), percent macrocytes (%Macro), serum erythropoietin (EPO) and soluble transferrin receptor (sTfr), since we had previously shown that these five variables were indicative of r-HuEPO use. RESULTS. The changes in Hct, RetHct, %Macro, EPO and sTfr in the Sydney trial were qualitatively very similar to the changes noted in our previous administration trial involving recreational athletes of similar genetic origin. Statistical models developed from Fisher's discriminant analysis were able to categorize the user and placebo groups correctly. The same hematologic response was demonstrated in Beijing athletes also administered r-HuEPO. INTERPRETATION AND CONCLUSIONS: This paper confirms that r-HuEPO administration causes a predictable and reproducible hematologic response. These markers are disturbed both during and for several weeks following r-HuEPO administration. This work establishes an indirect blood test which offers a useful means of detecting and deterring r-HuEPO abuse. Ethnicity did not influence the markers identified as being able to detect athletes who abuse r-HuEPO.  相似文献   
92.
The platelet-type thrombin receptor was the first member to be identified in a family of protease activated receptors (PARs) and has been designated PAR-1. We recently reported that the large granular lymphocytes (LGLs) in patients with proliferations of CD8+ cells co-expressed PAR-1 and the expression of PAR-1 correlated with the expression of CD57. Here we show, by three-colour immunofluorescence, that the LGLs from a patient with a rare CD4+ CD57+ monoclonal expansion also expressed PAR-1. Northern blot analysis confirmed the presence of high levels of mRNA for PAR-1 in these LGLs.  相似文献   
93.
Selection of women at high risk of breast cancer for initial screening   总被引:4,自引:0,他引:4  
Selective breast cancer screening refers to the intentional restriction of screening to only a high-risk subgroup of the total population of women at risk. Using data from the Canadian National Breast Screening Study, we explored methods of defining such subgroups. Discriminants were based on risk factor information collected prior to screening and were constructed using a training group of 77 cases and 400 controls. They were then tested on a separate group of 38 cases and 200 controls. Both simple risk factor counts and logistic models were utilized and separate analyses were performed for pre- and post-menopausal women. Using a logistic model, we were able to define a high-risk subgroup encompassing less than 40% of the test controls and over 85% of the test cases. Such a selection strategy, if implemented, might reduce initial visit mammography rates by up to 60% with only a small reduction in case detection. Other uses as determining the optimal age for initiation of screening are also discussed.  相似文献   
94.
Previously, we demonstrated that autoantibodies (AAb) in multiple sclerosis (MS) reveal site-specific binding and cleavage toward myelin basic protein (MBP) epitope library. We have found several fragments of MBP immunodominant in terms of AAb binding. Here, we applied these peptides to DA rats with induced protracted relapsing experimental allergic encephalomyelitis (EAE) most closely related to MS. DA rats with EAE induced by syngenic spinal cord homogenate in complete Freund's adjuvant were treated by nasal route with human MBP 46–62, 81–102, 124–139, 147–170, and Copaxone®. MBP 124–139 and 147–170 displayed only mild therapeutic effects but MBP 46–62 significantly reduced EAE, reflected by lower clinical scores and shorter EAE duration compared to controls.  相似文献   
95.
ObjectivesTo evaluate the accuracy and reproducibility of antimicrobial susceptibility testing methods in Burkholderia cepacia complex (BCC).MethodsMinocycline, ciprofloxacin, trimethoprim/sulphamethoxazole, meropenem, ceftazidime and chloramphenicol were tested against 155 BCC strains using broth microdilution at 35 ± 1°C (BMD35) in triplicate, then BMD at 30 ± 1°C (BMD30), agar dilution at 30°C and 35°C (AD30 and AD35), gradient strip (GS) and EUCAST standardized disc diffusion (DD) testing methods once.ResultsBMD35 reproducibility ranged from 70% to 84.5% for all agents. Correlations of MICs from BMD35 with BMD30 ranged from 63% to 85%, with AD35 from 32.9% to 87% and with GS methods from 36% to 83.9%. Essential agreement (EA) of MICs by GS with BMD35 ranged from 62.6% (trimethoprim-sulphamethoxazole) to 83.9% (minocycline). EA of EUCAST DD zone diameters using CLSI breakpoint criteria was between 85.8% and 97.4%, however Very Major Errors (VME) for trimethoprim/sulphamethoxazole were 31%.ConclusionsBMD at 35 ± 1°C was poorly reproducible for most agents and no method showed acceptable performance. Of particular concern were the GS results. Although this is the most commonly used method for determining MICs in laboratories, there was poor correlation with BMD35 for meropenem and trimethoprim/sulphamethoxazole. EUCAST DD correlated poorly with BMD35 MICs. This study confirms that no susceptibility method is capable of providing reproducible and accurate MICs when testing BCC.  相似文献   
96.
The purpose of this study was to investigate if obese children have reduced knee extensor (KE) strength and to explore the relationship between adiposity and KE strength. An observational case–control study was conducted in three Australian states, recruiting obese [N = 107 (51 female, 56 male)] and healthy-weight [N = 132 (56 female, 76 male)] 10- to 13-year-old children. Body mass index, body composition (dual energy X-ray absorptiometry), isokinetic/isometric peak KE torques (dynamometry) and physical activity (accelerometry) were assessed. Results revealed that compared with their healthy-weight peers, obese children had higher absolute KE torques (P ≤ 0.005), equivocal KE torques when allometrically normalized for fat-free mass (FFM) (P ≥ 0.448) but lower relative KE torques when allometrically normalized for body mass (P ≤ 0.008). Adjustments for maternal education, income and accelerometry had little impact on group differences, except for isometric KE torques relative to body mass which were no longer significantly lower in obese children (P ≥ 0.013, not significant after controlling for multiple comparisons). Percent body fat was inversely related to KE torques relative to body mass (r = ?0.22 to ?0.35, P ≤ 0.002), irrespective of maternal education, income or accelerometry. In conclusion, while obese children have higher absolute KE strength and FFM, they have less functional KE strength (relative to mass) available for weight-bearing activities than healthy-weight children. The finding that FFM-normalized KE torques did not differ suggests that the intrinsic contractile properties of the KE muscles are unaffected by obesity. Future research is needed to see if deficits in KE strength relative to mass translate into functional limitations in weight-bearing activities.  相似文献   
97.
Retroperitoneal lumbocrural abscess occurred in 12 patients of 231 with Crohn's colitis or ileocolitis. Although all patients with this complication fell within the group of 175 ileocolitis patients, at least four originated in fistulous tracts of the colon. Eleven of the 12 abscesses developed spontaneously as the first major complication of the disease. The prominent clinical features included pain radiating down the thigh, hip joint flexion, difficulty in walking, hydronephrosis and hydroureter. Internal and external fistulas were significantly more common in the abscess group of 12 patients than in the 219 patients without retroperitoneal abscess. Radiological evidence of granulomatous disease was found in all patients; fistulous tract formation was characteristic and the development of extraperitoneal gas bubbles, in four patients, pathognomonic of abscess with gast-forming organisms. In the presence of established retroperitoneal abscess, the surgical sequence suggested is drainage synchronous with, or followed by diversion and ultimately definitive resection. Resection with anastomosis should not be carried out in the presence of an acute inflammatory process with frank abscess or free pus communicating with the peritoneal cavity. The spontaneous development of retroperitoneal abscess is a serious development in the natural history of Crohn's (ileo) colitis. It frequently heralds the first of a series of operative procedures to deal with the abscess. It sequels are enterocutaneous fistulas and further extension of the disease process.  相似文献   
98.
Thong BY  Thumboo J  Howe HS  Feng PH 《Lupus》2001,10(4):304-308
Life-threatening angioedema involving the upper respiratory tract is an uncommon manifestation in systemic lupus erythematosus (SLE). We report three patients in their late adolescence who had laryngeal oedema causing airway obstruction and requiring mechanical ventilation during active disease following symptoms of a respiratory tract infection. All of them had major organ involvement from lupus and none had a family history of hereditary angioedema (HAE). The mechanisms of angioedema in SLE are heterogeneous. There has been little evidence so far of anti-Cl inhibitor (Cl INH) autoantibody in SLE patients with angioedema. These are the first three cases reported in the literature of life-threatening angioedema following respiratory tract infection in SLE.  相似文献   
99.
The way students are taught and evaluated is changing, with greater emphasis on flexible, individualized, learner‐centered education, including the use of technology. The goal of assessment is also shifting from what students know to how they perform in practice settings. Developing educational materials for teaching in these ways is time‐consuming and can be expensive. The Portal of Geriatrics Online Education (POGOe) was developed to aid educators in meeting these needs and become quicker, better‐prepared teachers of geriatrics. POGOe contains more than 950 geriatrics educational materials that faculty at 45% of allopathic and 7% of osteopathic U.S. medical schools and the Centers for Geriatric Nursing Excellence have created. These materials include various instructional and assessment methodologies, including virtual and standardized patients, games, tutorials, case‐based teaching, self‐directed learning, and traditional lectures. Materials with common goals and resource types are available as selected educational series. Learner assessments comprise approximately 10% of the educational materials. POGOe also includes libraries of videos, images, and questions extracted from its educational materials to encourage educators to repurpose content components to create new resources and to align their teaching better with their learners' needs. Web‐Geriatric Education Modules, a peer‐reviewed online modular curriculum for medical students, is a prime example of this repurposing. The existence of a robust compendium of instructional and assessment materials allows educators to concentrate more on improving learner performance in practice and not simply on knowledge acquisition. It also makes it easier for nongeriatricians to teach the care of older adults in their respective disciplines.  相似文献   
100.
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